Method of making carpet underlay

Abstract

A method of making a carpet underlay is provided wherein the underlay is comprised of a sponge rubber body having a load-carrying surface defined by a plurality of cooperating closed-area coplanar portions which define the major part of the area of a plan view of such body.

1. A method of making carpet underlay comprising the steps of forming an endless conveyor means of heat resistor wire-like mesh material having openings with heat resistant elongated flat strips inserted therein, forming a sheet of elastomeric material, depositing said sheet on said mesh material, heating said sheet to soften it and to cause it to droop around said mesh material, forming a plurality of U-shaped channels in the upper surface of said sheet as a result of said droop, limiting said droop on the lower surface of said sheet by means of said strips, further utilizing said strips to prevent said sheet from passing completely through said openings in said mesh material and simultaneously expanding 
     
     
       2. The method of claim 1 in which said step of heating is provided by a 
     
     
       3. The method of claim 1 including the step of forming said mesh material into a plurality of undulating members held together by common tie members to form said openings.